The tax law is quite specific as to requirements for qualifying for the 90 day rule for foreign service. Working a regular cycle of 2/4/6 weeks in foreign service and 2/4/6 weeks off in Australia (or out of Australia for that matter), does not interfere with the continuity required for the 90 day rule. In other words, Australian tax payers still qualify for the 90 day rule tax break whilst touring from Australia.